Pulmonary Vascular Disease Flashcards
Which class of pulmonary HTN therapy is most likely to cause derranged LFTs?
Endothelin Receptor antagonists - Bosentan, Ambrisentan, Macitentan need monthly monitoring of LFTs
You see a 56-year-old woman in the clinic who is being treated for pulmonary hypertension. She reports feeling better and her activity levels have also improved but you notice a worsening of her leg oedema, which the patient is concerned about. The patient’s dose of her furosemide has been increased and her leg oedema is still getting worse. She is currently taking tadalafil and ambrisentan.
What should be done next to address her leg swelling?
Switch Ambrisentan to Macitentan
Leg oedema can be result of right heart failure from Pulmonary HTN and it’s a side effect of Ambrisentan therapy . Sx improving and oedema worsening despite furosemide so best option is to switch meds
What are the absolute contraindications to systemic fibrinolysis/ thrombolysis ?
- Hx of haemorrhagic stroke or stroke of unknown origin
- Ischaemic stroke within last 6/12
- CNS Neoplasm
- Major Trauma, surgery or head injury in last 3/52
- Bleeding diathesis
- Active bleeding
What are the relative contraindications to systemic fibrinolysis/ thrombolysis ?
- TIA in last 6 months
- Oral anticoagulant
- Pregnancy or 1 week post partum
- Non compressible puncture site
- Traumatic Resuscitation
- Refractory HTN ≥ 180
- Advanced liver disease
- Infective Endocarditis
- Active peptic ulcer
What set of follow up investigations required for stable PH?
The 2022 pulmonary hypertension guidelines specify a follow-up monitoring plan in case of a stable case of pulmonary hypertension (which is the case in this scenario). It recommends WHO-FC, a 6-minute walk test, ECG, ABGs or pulse oximetry, and bloods including NT pro-BNP be performed. RHC is more useful in the context of change in the treatment of worsening clinical symptoms.
What is the most common genetic abnormality in cases of heritable PAH?
Heterozygous mutations in the BMPR2 gene remain the most common genetic abnormality implicated in cases of heritable PAH, accounting for approximately 75% of hereditary cases. To date, a number of other genes also implicated in PAH have been identified, including ALK1 and endoglin. PAH patients with BMPR2 mutation are less likely to respond to vasodilator treatment, develop clinical manifestations of the disease at a younger age, and have more severe haemodynamics and a worse prognosis.
Lifetime pentrance 25% (thought a 2nd hit req)
What are common side effects of prostacyclin analogues ?
Headache and chest pain
GI discomfort and flushes
(Blurred vision and embolism very infrequent)
What is the definition of Pulmonary HTN?
An mPAP of >20mmHg at rest as assessed by aright heart catheterisation
How do you differentiate between pre and post capillary and combined ?
Pre Capillary Component :
PVR> 2 woods units (if severe will be >5WU)
Post capillary Component:
PVR ≤ 2 woods units
Combined Post and Pre Capillary PH: PVR >2 wood units
What are the 5 classes of pulmonary HTN?
I. Pulmonary Arterial Hypertension
II. PH associated with Left Heart Disease
III. PH associated with lung disease / hypoxia
IV. PH associated with pulmonary artery occlusion (CTEPH most common)
V. PH w unclear or multifactorial mechanism
What are the echo probabilities assigned?
TRV < 2.8 LOW
TRV 2.9 -3.4 INTERMEDIATE
TRV >3.4 HIGH
(NB if LOW but other signs , ie high PASP then becomes intermediate)
What is the gold standard investigation for diagnosis of PH?
Right heart catheter
What treatment is given for patients with PAH without cardiopulmonary co-morbidities and non vasoresponders who are low/intermediate risk?
Endothelin Receptor Antagonist (Ambrisentan , Macitentan, Bosentan)
AND
PDE5i
(Sildafenil, Tadalfil)
What treatment is given for patients with PAH without cardiopulmonary co-morbidities and non vasoresponders who are high risk?
Endothelin Receptor Antagonist (Ambrisentan , Macitentan, Bosentan)
AND
PDE5i
(Sildafenil, Tadalfil)
AND
Prostacyclin analogues
(Prostacyclin, epoprostenol, iloprost)
What model do we use to assess risk in PH follow up?
4 strata model
What model do we use to assess risk for PH initially ?
3 strata model
What is included in the 3 strata model risk assessment for PH?
Signs of RHF
Progression of sx
Syncope
WHO FC
6MWT
CPET
Biomarkers (BNP)
Echo
MRI
Haemodynamics
What is included in the 4 strata model risk assessment for PH?
WHO FC
6MWT
BNP/ NT-Pro BNP
If during follow up of low or intermediate patient not improving , what can we do?
- add prostacyclin receptor against (Selexipag)
- switch PDE5i to soluble guanylate cyclase stimulator (Riociguat)
If during follow found to be high or intermediate high what can we add in?
SC / IV prostacyclin analogue
Lung Transplant
What treatment is given for patients with PAH with cardiopulmonary co-morbidities and non vasoresponders ?
Endothelin Receptor Antagonist (Ambrisentan , Macitentan, Bosentan)
OR
PDE5i
(Sildafenil, Tadalfil)
What treatment can be used in PH associated with ILD?
Inhaled Trepostinil (procyclin analogue)
What dose mPAP of >20mmHg at right heart cath indicate?
Pulmonary HTN
What does PAWP > 15mmHg indicate ?
Likely PH assoc with LHD
What does PAWP <15mmHg indicate ?
Need to look at cardiac output
If Low /Normal: Pre- Capillary PH (ie PAH, PH - resp , CTEPH , multi factorial)
If high: Consider left to right shunt - look at O2 Sara if >90% then in keeping with L>R shunt
So what dynamics would you expect to see on RHC for PAH?
mPAP > 20 mmHg
PAWP ≤ 15mmHg
PVR > 2 WU
What vasoreactive agents do we use for vaasodilation testing ?
Inhaled Nitric Oxide
Inhaled Iloprost
IV epoprostenol
What is a positive vasoreactive test ?
Drop in mPAP of ≥ 10mmHg and to <40mmHg with increased or unchanged cardiac output
What is the gene associated with Pulmonary Veno-Occlusive disease ?
E1F2AK
What percentage of systemic sclerosis patients have PAH?
10%
Should have annual evaluation
What is the prevalence of PH ?
1% in the general population
What is the leading cause of PH globally ?
Left Heart Disease
What drugs/ toxins associated with PAH?
Aminorex (WL stimulant drug)
Benfluorex (appetite suppressant)
Dasatinib
Dexfenfluramine
Fenfluramine
Metamnephrines
Toxic Rapeseed oil
Some association with alkylation agents such as cyclophosphamide , amphetamines , cocaine , against Hep C
What is the cardinal early sx of PH ?
Dyspnoea on exertion
What is the first line non invasive diagnostic investigation for symptomatic PH?
Echo
What bloods are recommended in PH?
Routine biochemistry
Haematology
Immunology
HIV
TFTs
In PH what is WHO functional class 1?
Patient without limitation to physical activity
In PH what is WHO functional class 2?
Pt with slight limitation to physical activity , comfortable at rest
In PH what is WHO functional class 3?
Marked physical limitation to activity , comfortable at rest
In PH what is WHO functional class 4?
Pt w PH unable to carry out any physical activity without symptoms , symptomatic at rest
What is the estimated 1 year mortality for Low Risk PH?
<5%
What is the estimated 1 year mortality for Intermediate Risk PH?
5-20%
What is the estimated 1 year mortality for High Risk PH?
> 20%
When to perform RHC in PH?
At baseline
Repeats not usually helpful
What management recommended in PH in general?
Supervised exercise
Immunisations
Diuretics if RV failure
LTOT if PaO2 <8
Correct iron stores
In flight O2 <8 at sea level
Anticoagulation not usually recommended
Contraceptive advice if female and child bearing age
Are there teratogenic effects of PH meds ?
Endothelia Receptor Antagonist
Riociguat
What percentage of patients with PAH are vasoresponders ?
<10%
Does a favourable vasodilator response predict a favourable long term response to CCBs?
No
What CCBs are predominantly used in vasoreactive +ve PAH patients ?
Nifedipine
Diltiazem
Amlodipine
What are the indicators for referral to lung transplant ?
ERS/ESC High Risk or REVEAL score >10
Progressive hypoxaemia especially in PVOD or PCH
Progressive but not end stage liver / kidney dysfunction due to PAH or life threatening haemoptysis
What do you in PAH caused by drugs /toxins
Stop offending drug
Reassess once off for 3-4 months
If no improvement consider tx as per PAH
NB prev appetite suppressants and toxic rapeseed oil, today metamphetamines , interferons and some TKI
Who should be screened for PH?
Systemic sclerosis
Assessment of liver transplant
BMPR-2 mutation carriers
First degree relative of HPAH
What is the investigative work up for CTEPH?
VQ Scan and Echo
What is the treatment of CTEPH ?
Lifelong anticoagulation for all w VKA
If Operable: Pulmonary endarterectomy tx of choice
If not operable : Medical therapy with Riociguat
What are the risks for CTEPH?
Idiopathic PE
Increased Factor 8
Abnormality in fibrinogen
APL or lupus
Large clot burden
Splenectomy
Chronic inflammation
Hypothyroidism
Previous cancer
When do we use BPA in CTEPH?
For those who are inoperable or have residual PH after PEA and distal obstruction amenable to BPA
What kind of drug is Riociguat?
A stimulator of soluble Guanylate Cyclase
Who gets Riociguat in CTEPH?
Symptomatic patients with inoperable CTEPH or persistent / recurrent PH after PEA
How do we treat CTEPD - chronic thromboembolic disease (without Pulmonary HTN)
Long term anticoagulation
What causes Class V PH?
Haematological disorders
- Chronic Myelproliferative
- CML
- PV
- Idiopathic Myelofibrosis
- Essential thrombocytopenia
Inherited / Acquired chronic Haemolytic Anaemia:
- Sickle cell disease
- B thalassemia
- Spherocytosis
- AI disorders
Systemic:
- Sarcoidosis
- Pulmonary Langerhans Cell Histocytosos
- Neurofibromatosis Type 1
Metabolic
- Glycogen storage disorders
- Gauchers
Chronic Renal Failure with or without haemodialysis
Pulmonary tumour thrombotic microangiopathy
Fibrosing mediastinitis
What are the indicators that PE patient needs to be managed as an inpatient ?
- Haemodynamic instability (HR>110, SBP <100 , req inotropes , req thrombolysis)
- O2 sats <90%
- Active bleeding or major risk of bleeding (recent surgery , prev IC bleeding or uncontrolled HTN)
- On full dose anticoagulation at time of PE
- Severe pain (req opiates)
- Other medical co-morbidities
- CKD stage IV or V or severe liver disease
- HIT within last year and where no alternatives to repeating heparin treatment
- Social reasons
What are the WELLs cut offs for PE?
> 4 PE likely
<4 unlikely
What is included in WELLs for PE?
Clinical signs and symptoms of DVT (3)
An alternative dx less likely than PE (3)
HR >100 (1.5)
Immbolisation for >3 days or surgery last 4/52 (1.5)
Previous PE/DVT (1.5)
Haemoptysis (1)
Malignancy with treatment within 6/12 or palliative (1)
What do you do if WELLs score is > 4
CT-PA
Or
if allergic to contrast / severe renal impairment (eGFR <30) / high risk of irradiation assess suitability for VQ scan
What do you do if Wells score <4
D-Dimer
If +ve CT-PA
If -Ve think alternatives
What is the anticoagulation as per NICE for PE with no renal impairment, antiphospholipid or haemodynamic instability ?
Rivaroxaban or Apixaban
What is treatment for CrCl 15-50 with PE?
Apixaban
Rivaroxaban
LMWH for at least 5/7 then Dabigatran /Edoxaban
What is treatment for CrCl <15 with PE?
LMWH
UFH
What is treatment for PE with cancer ?
Consider DOAC
LMWH
LMWH and VKA
What is treatment for PE with Antiphospholipid ?
LMWH (for at least 5/7 or until INR at least 2 on 2 consecutive readings) and VKA
What are the extremes of body weight where modifications req in PE tx ?
<50kg
> 120 kg
In patients who decline anticoagulation with PE what can be given to them ?
Aspirin
What is the risk of VQ scan in pregnant women?
Slight increase of childhood cancer but associated with reduced risk of maternal breast cancer